Warp cord tensing means for looms



Jan. 31, 1961 F. H. BLAKE 2,969,313

WARP CORD TENSING MEANS FOR LOOMS Filed April 21, 1959 s Sheets-Sheet 1FREDERICK H. BLAKE INVENTOR.

Jan. 31, 1961 F. H. BLAKE WARP CORD TENSING MEANS FOR LOOMS 3Sheets-Sheet 2 Filed April 21. 1959 INVENTOR. FREDERICK H. BLAKE Jan.31, 1961 F. H. BLAKE WARP CORD TENSING MEANS FOR LOOMS 3 Sheets-Sheet 3Filed April 21, 1959 FIG MAGNETIC CLUTCH WIND-UP UNIT RELEASE OF BRAKECOMPLETED BEATER HITS MATERIAL ALREADY WOVEN WITH NEW STICK IBRAKE ONTENSION SHAFT-LOCKED J START OF BRAKE SETTING FIG-IO if STICK LOADINGTIME FIG;

T0 SWITCH INVENTOR.

FREDERICK H BLAKE United States Patent f WARP CORD TENSING MEANS FORLOOMS Frederick H. Blake, 1045 91st NE., Believue, Wash.

Filed Apr. 21, 1959, Ser. No. 807,849

7 Claims. (Cl. 139-104) This application relates to stick weaving loomsand more particularly to tensioning means for warp cords used on stickweaving looms. This present application is a continuation-in-part of aUS. patent application filed by me under Serial No. 549,361 on November28, 1955, and entitled Stick Weaving Loom.

The weaving of slat-like materials of small dimensions into materials ofsuflicient width so that it can be hung with the slats vertical orhorizontal and serve as curtain material, room dividing material, andalso as closures for door openings, has developed special problems,outstanding is the fact that is it found necessary to use a greaterbeating force than in other looms, in order that the successive slatswill be driven home uniformly, close together, and in a parallelrelationship at right angles to the longitudinal axis of the wovenmaterial. In such Weaving the warp cords are normally much stronger thanin the weaving of cloth and similar materials and in order to functionproperly with the heavier beating strains imposed upon the cords a muchgreater tension is of necessity imposed upon them. In such weaving it issufiicient to have warp cords pass through spring compressed ten sioningdevices. Such devices normally can safely and with uniformity imposetensions of from O to approximate of one pound. However in this form ofweaving, wherein sticks are employed, it has been found most desirableto employ greater tensions of the order of ap proximately three poundson each of the warp cords. This is far beyond the capacity of the typeof tensioning devices which rely upon friction caused by two parallelsurfaces tending to grip the cords. In this present invention, rollertensioning means are provided to the end that very substantialtensioning can be provided, and it has been found most desirable to usethe compression of friction type tensioners in association with theroller means, wherein the older form of tensioners may be consideredback tensioners to maintain snubbing strain on the roll tensioners 17and 18 and as adjusting or Vernier means to achieve the exact tensionrequired on certain of the cords, or to provide uniform tensionthroughout.

A principal object of this invention therefore is to provide means whichare capable of successfully and uniformly applying the increased tensionrequired on the warp threads when the same are used in the weaving ofslat or stick materials, and to maintain constant and even tension onthe longitudinal threads while periodically inserting thin slats orstrips of stiff material at right angles to these threads.

A further object of this present invention is to provide shaft meansaround which the warp cords are wrapped and which cords provide therotative force for the shafts which are otherwise not provided withturning means.

A further object of this invention is to provide roller tensioning meanswherein the roller may be provided with friction drag means so that thetensioning of the cords by the roller can be varied Within operationallimits, and under extreme cases of tensile requirements to Patented Jan.31, 1961.

provide a roughening of the cord engaging surfaces to in-- crease thefriction available.

A further object of this invention is to provide a plurality of rollersturning at the same angular speed but within the rollers, themselves,are of different diameters.

A further object is to provide intermittent braking means for stoppingthe rotation of the tensioning roller or rollers during the beatingperiod and having this same interconnected with the rollup roll of theloom so as to synchronize the dead periods of the two rolls, and thusprevent the slackening of the warp cords or placing unusual strains onthem.

Further objects, advantages and capabilities will be ap parent from thedescription and disclosure in the drawings, or may be comprehended orare inherent in the device.

In the drawings:

Figure 1 is a plan view of one type of loom to which this presentinvention may be successfully applied;

Figure 2 is a side elevation of a portion of the loom of Figure 1;

Figure 3 illustrates in a fragmentary side elevational view the brakingmeans for a tension producing roller and switching means therefor;

Figure 4 is a perspective view in fragmentary form showing two paralleltensioning shafts and the manner in which the warp cords are woundaround the same; 7

Figure 5 illustrates a common form of back tensioning means which hasbeen found very satisfactory for use with this present tensioning meansprovided by one or more of the shafts of Figure 4 and to act as aVernier or adjusting means therefor;

Figure 6 is a fragmentary elevation partly in section illustrating oneof the switches actuating the electrical system;

Figure 7 is a schematic electrical diagram illustrating the electricalconnections between the brake of the tension roller and the motive powerfor the wiudup roll to insure synchronous action of these two means; VFigure 8 is a top plan view showing the motor which drives the winduproll and showing the use of a magnetic clutch as a means for stoppingand starting the windup roll;

Figure 9 is a fragmentary vertical sectional view of the adjustablefriction means, taken along line 9-9 of Figure Figure 10 is adiagrammatic view showing the proportion of a single stick weaving cycleemployed to place the stick, to complete the beating, and illustratingthe proportional time to complete the shaft braking cycle.

Figures 1 and 2 show, in addition to the subject matter of this presentinvention, sufiicient of a typical stick weaving loom so that theassociation of the tensioning means with a loom of this type can be morethoroughly disclosed.

Referring more particularly to the disclosure in the drawings,throughout which like reference characters indicate like parts, thenumeral 10 designates the frame of a stick weaving loom of the typesuitable for the employment of my present tensioning means.

Fixedly secured to frame 10 is a vertically disposed frame memberadapted to support a plurality of shafts 11, upon which are revolvablypositioned a large number of spools of cord 12 forming the warp. Afterleaving spools .12, cords C are lead to convenient guiding means so asto bring the cords substantially in alignment with their final portionon the loom. The cords are then passed through grommeted openings in theflange of the tensioner supporter 13 and divided by collared bolts 14,as will probably be best understood from a study of Figure 5 of thedrawings. The cords are next crossed over to the opposite hand andplacedbetween the spring loaded flanges of the tensioners 15. The threads arethen recrossed and lead around the collared bolts 16 through grommetedholes in the second flange of the tensioner support. T ensioners 15 are.well known in this field and are used to provide that the spring urgedplates maybe adjusted to provide the desired frictionalengagement withthe cords within their capacity.

The dependable working range of tensioners of the type illustrated isfrom to% of one pound. Asapproximately three pounds of tension isrequiredin-this loom the bulk of the tension load is achieved byaplurality of rolls, to be described. ,Thetensioners 15 may therefore beconsidered back tensioners for the roll tensioners and as an adjustingor vernier means to achieve the tension required on certain of thecords, or ,to provide ,llniform tension throughout.

The threads or'cords C are thempassedgover andonce around shafts17 and118, whichrshafts are mounted transversely of the frame and are at rightangles ,to the direction of movement of the threads: The threads firstare passed. over shaft 17. ,undersaid shaft and brought through to theright of the respective-sides. They are then passed over shaft 18, under;said shaft and brought through to the left of their respective sides.This shiftingv from rightto left compensates for the laygortwist of .thethreads which arecord-like and consist ofthe plurality of yarns whichare twisted into a thread or cord. It has been found that unless thisarrangement is provided, the threads willgtravel to the right at alltimes due to the lay of the threads and tension will be increased by,irregular amounts and, in some cases, may bind andbreak the threads.Shaft 18 is of slightly larger diameter than shaft 17, this differencebeing in the order of three thousandths of an inch (.003") on an overallshaft diameter of one and three eighths inches (1%"). Means are providedto insurethat shafts 17 and 18, however,.travel at the same rotary orangular speed. One means for providing this relationship is illustratedin Figure 2, in which it will be noted that a sprocket is secured toeach of shafts 1'7 and 18 and they in turn are connected by a chain 29.A preferred arrangement employs an idler, as illustrated at 19,.so thatadjustment can be made on the connecting chain.

Within the idler sprocket a torque adjustment device of conventionaldesign maybe advantageously employed. A simplified form of torque deviceis illustrated in Figure 9 in which bearingbolt 21 is. keyedto and;supported by frame 10. A pair of coacting thrust washers 22 and 26 areemployed, the same being keyed, 22 to bolt 21 and 26 to sprocket 19.Frictional adjustment, which controls the torque available through chain'29 to shafts 17 and 18, is made by lock nuts 27 and washer 30. Shafts17 and .18 are operated solely by the frictipncreated by the wrap-aroundcords'C, which are under tension supplied by the main woven materialtake-up roll 58. Shaft 18 having a larger diameter than shaft17, butoper- 'ating at the same r.p.m., puts a tension of a few pounds on thethreads. This provides a differential between the two rolls 17 and 18.The friction clutch or torquede vice incorporated in the idler may beemployed to slow down the speed of both rolls slightly and thus put anoverriding tension on the cords. This same means may be used if only oneof the shafts is employed, asmay be desirable where maximum-tension isnot required. In such cases it is usually desirable to increasethediameter of the shaft.

' The threads or cords are passed to a suitable shedding aarrangementwhere the strips are introduced between the cords as weaving requires.'With the placement of each strip the beater, as 28, must bemoved-forward to properly seat the successively positioned strips. Theshedding .and beating arrangements form no directpart of thisapplication but one example is given in my c0-pendingaapplication,.Serial No. 549,361. However, during .4 the beating action the powerapplication to the woven material windup roll 58 needs to be interruptedand during the period the roll 58 is stationary shafts 17 and 18 must bestopped and held in order to hold the warp threads or cords undertension. The necessity of precise sequential timing indicates the needof joining the actuating means for the beater operation, the windup rolland the brake for rolls 17 and 18 in a single electrical unit. Referenceis now made to Figure 7 in which the essential electrical elements areshown schematically.

In the operation of this equipment, startingwith introduction of a newstrip S, the desirable sequence is substantially: as strip -S completesits movement through the space provided betweencords Cit trips theelectric switch 46 which actuates a suitable beater bar 28 and itssupporting framework which drives strip S into its final position in thewoven material and then returns the beater bar to its rest position. Thefinal return movement of the beater bar-assembly .partially rotatesshaft 54and actuates switch 44,,which switch has. a two-fold purpose.Referring back to the period when the beater bar strikes the strip ofwood home to its final position, the bar.engages bayonet member-55attached toswitch .56 and this switch energizes the magnetic clutch 70controlling windup motor 57. Bayon et member 55 is urged upwardly byspring means to de-energize switch 56. .When sticks S overlay camportion 73 the bayonet member is depressed and switch56 energized andthe windup roll is operated once for each;stick until the'sticks are allin place. It is to be noted that switch 56 merely energizes the magneticclutch switch, but doesnot complete the circuit. The circuit is actuallycompleted when countershaft 54 by its rotation, caused by the return ofthe beater bar, actually trips switch 44.

When the windup motor 57,. which serves to wind up the. entire bolt ,of.material that has been woven, is in operation the windup roll 58 ismoved .by a chain reduction drive 159 connected to the magnetic clutch70 by the right angle gear box 154. When the windup roll has moved to apoint allowing. bayonet member..55 to return to its normal position thecircuit is broken. The magnetic clutch is instantaneously engaged andsolenoid 45, through a suitable linkage, actuates brake 59 on shaft 18.It is to be noted that throughout this mechanism accurate timing is veryessential and in order to actuate the parts, some of which arerelatively large, it has'been found desirable that the main energizingbe accomplished by electric motors or air cylinders, neither one ofwhich function instantaneously; and it is for this reason that apreferred formv of construction employs solenoid releasing means havingactuating members of small mass to the end that accurate and exacttiming can be achieved.

' Fig. 10 illustrates by diagram the proportion of a complete cyclerequired to feed and weave onestick in place. In this illustration thecomplete cycle is assumed to be one second. '-It is to be noted that thetime toload one stick into the shed is 0.4 second, and that loadingstarts at 0.0 second. The time to shift the shed is 0.1 second startingat 0.4 and ending 0.5. The heater, being an elementof appreciable mass,requires .25 second starting at 0.4 to move into contact with the newstick S. The heater dwell time 0.1 second starting at 0.65 is consumedin driving the stick homeand holding it in position until the beaterback portion of the cycle starts at 0.75 second. 7 The brake on shaft 18must be locked on, during the period, 0.5 to 0.9 but the brake requires.05 second to set and the same period to release. Power must also bedisconnected from the windup roll 58 during the healing period, when thebrake is locked. The windup roll has the tension of all the cords on itand stops as soon as power is interrupted.

It is believed that it will be clearly apparent from the abovedescription and the disclosure in the drawings that the inventioncomprehends a novel construction of a warp cord tensing meansfor looms.

Having thus disclosed the invention, I claim:

1. A cord tightener for a loom, comprising: a pair of tension shaftsextending transversely of a loom frame in closely spaced apartrelationship and said shafts rotating at different peripheral speeds,and the warp cords in said loom having turns about said tension shafts;means are provided for insuring that said pair of tension shafts willrotate at the same angular speed and adjustable friction means adaptedto vary the force required to revolve said shafts and thus provide anadditional means for varying the tension imposed on said warp cords.

2. A cord tightener for a loom, comprising: a pair of tension shaftsextending transversely of a loom frame in closely spaced apartrelationship and said shafts rotating at different peripheral speeds,and the warp cords in said loom having turns about said tension shafts;said pair of tension shafts are provided with roughened warp cordengaging surfaces, each being uniformly configured throughout theirrespective portions which are engaged by said warp cords.

3. A cord tightener for a loom, comprising: a loom frame supporting cordfeeder means at one end and a driven woven material roller at the other;a spring loaded tensioner next to said feeder means which has opposedadjustable spring-loaded surfaces between which cords pass and whichrestrain said cords and a tension shaft between said tensioner and saidroller, said tension shaft having electrically operated brake meansadapted to stop the rotation of said tension shaft when it is fullyapplied; said tension shaft extending transversely of the path of travelof cords and the cords passing around said tension shaft and saidtension shaft having speed control means whereby it may be caused torotate at peripheral speeds of less than the lineal speed of the cordsafter said cords leave said spring-loaded tensioners.

4. The subject matter of claim 3 in which said tension shaft has itscord engaging surface uniformly roughened throughout its length toincrease the friction of the cord as it passes around said tensionshaft.

5. The subject matter of claim 3 in which said driven 6 woven materialroll and said tension shaft are provided with means synchronizing theinterruption of the motive power of said roll and the operation ofactuating means for said electrically operated brake to insure thestopping of said roll and said shaft during the beating cycle of a loomto which said cord tightener is operatively secured.

6. A cord tightener for a loom, comprising: a loom frame supporting cordfeeder means at one end and 'a power driven woven material roller at theother, a spring loaded tensioner next to said feeder means which hasopposed adjustable spring-loaded surfaces between which cords pass andwhich restrain said cords and a pair of tension shafts between saidtensioner and said roller extending transversely of the path of travelof cords and the cords passing around each tension shaft and saidtension shafts having means whereby they rotate at different peripheralspeeds with the lesser peripheral speed occurring on the shaft which thecords pass around first after leaving said tensioners and brake meansfor stopping the rotation of said tension shafts.

7. The subject matter of claim 6 in which said driven woven materialroller and said pair of tension shafts are provided with electricallyoperated means synchronizing the interruption of motive power of saidroll and the actuating means for said power operated brake to insure thestopping of said roll and said shaft during the beating cycle of a loomto which said cord tightener is operatively secured.

References Cited in the file of this patent UNITED STATES PATENTS 57,898Hasecoster Sept. 11, 1866 624,658 Kelly May 9, 1899 763,628 Petersen-3.. June 28, 1904 819,742 Draper May 8, 1906 1,703,276 Lloyd Feb. 26,1929 2,480,395 Clark Aug. 30, 1949 2,833,314 Shaw May 6, 1958

